Hate this blazer

My 98 blazer is losing fuel pressure as soon as it gains it. When the key is turned on it goes up around 64 lbs which is normal but immediately starts falling off and is down around 6 lbs within seconds. I have inspected for leaks from the tank to the plenum and found none. This leads me to believe it may be the pressure regulator inside the plenum or even worse leaking off inside the plenum itself. I'm going to peel the plenum off shortly and try to locate the problem. Any input or guidance on this would help greatly. I know it will be a good reliable vehicle once these nuisances are worked out but as you know it becomes stressful. Thanks in advance for any advice.